Improvement in sewing-machine



nmol sans @tutti @Witte ALONZO PORTER, OE ROCHESTER., NEW YORK, AssIcNOR To HIMSELE, ELI- sHA c. MARSHALL, AND SARAH R. YOUNG, OR SAME PLAGE.

letters Patent No. 99,?04, dated February 8, 1870.

mrRovEMENT IN SEWING-MACHINE.

The Schedule referred to in these Letters Patent: and making part cf lthe same To all whom 'it ana-y concern:

Be it known that I, ALONZO PORTER, assigner to myself, ELISHA G. MARSHALL, and SARAH R. YOUNG, all of the city ot' Rochester, county of Monroe, and State of New York, have invented a certain new and useful Improvement in Sewing-Machines; and I do hereby declare that the following is a full and exact description ot' the same, reference beingr had to the accompanying drawings, in which- Figure l is a side `elevation of' my improved machine.

Figure 2, a similar view, but at right angles to-tig. 1.

Figure 3, a top View of the front end of the frame, showing the connection and attachment of the clothpresser.

Figure 4, a view, showing the cam of the driving wheel, and the connection of the pitmau-rod therewith.

Figure 5, a diagram, showing a plan of the parts connected with the feed-bar and needle.

Like letters ot'reierence indicate corresponding parts in all the figures.

M y invention consist in the arrangement ot the operating-parts, as hereinafter described.

In the drawingsf A indicates the frame, having openwork bars or arms, a a, and a baseplate, b, t'or attaching to a table.

lwo shai'ts, B C, are mounted in the frame, the upper serving to give motion to the needle, while the lower gives motion to the feed-mechanism, and also the hook which holds the loop of threadavhile the needle goes up.

At. one end of' the upper shaft is mounted a crankwheel, D, having, preferably, a groove in its periphery for the reception ot' a bami, which connects with a mo'- tive-poner below, in the ordinary manuel'.

At the opposite end of the upper shaft is situated a crank-liezul, E, the pin c ot' which rests in a slot-ted har, G, attached rigidly to thenecdle-har H. The revolutions of the cranklhead give the lip-and-dewn motion to the needle-bar.

The outer end ofthe lower shaft has a crank-head, I, with the pin of which connects a pitman, K, passing upward, and having a loop, (l, at the top, which rests on au eccentric, L, which forms a solid part ot' the driving-wheel D. Every revolution Ot' the latter imparts simply a rocking' motion to the crank-head I, and, conset'luently, to theshai't C.

To the opposite end ot' the lower shaft is secured a cani, M, and hook-head N.

At every tnwardinotion of the cam, it strikes lug f ot' the feed-har O, thereby causing it to throw the cloth along upon cloth-plateP-.

lhc stem ot' the feed-bar rests upon an eccentric surface, g, of the cam, which, in the forward motion, elerates the feed-barsniciently to make ithold in the cloth.

lhe reverse motion of the feed-bar is produced by a screw, It, which passes through a bearing, ,'of the bar,

in such position-as to be struck by the cam M, in its "buck action. By turning this screw up`, more or less,

it is apparent that the throw ot the feed-har will be changed, and, consequently, the length of the stitches adjusted as desired.

The rear end of the feed-bar is held up by a spring,

next descent. This forms a lock-stitch, with a single thread, that will not unravel under ordinary circumstances.

Tile crank I is provided with a curved slot, in which the pin a, that connects with the pitman K, is secured, and may be adjusted to properly time the operation ot' the parts.

The cloth presser-foot R has slot, p, through which the needle passes; and this slot is madeopen through the side, to allow the footto swing around free ofthe needle, which is necessary in threading, since the eye' of the needle does not come high enough to free t'rom the presser in its ordinary-,positioni.

rl`he shaft r ofthe presser turns free'in bearings q q ot' the frame; and, at t-he upper end, it hasa roller, s, whose shaft, t, rests in an open slot, u, ot' the upper bearing. This keeps it in positioniu working.

W'hcn it is desired to raise the presser, to turn it' around, the roller s strikes ou top the hearing g, the shaft t, at the same time, freeing iiom sloth, as in tlg: 3. I Y I The tension-device, for holding thc thread, consists simply ot'two disks, o c, one being fast and the other loose, and a. spring and nut, lw x, pressing down upon the loose one. The thread, passing between the disks, receives any desired amount oft'rietion, by turning down the nut.

sVhat I claim as my invention, and desire to secure by Letters Patent, is-

' The rotating shalt B, provide'tl with the mechanism for operating the needle-har and needle, the fly-wheel D, having the eccentric L cast with it in one piece, the pitman K, the adjustable stud n., thev crank-head I having the curved slot, the working-shaft O, the ad instable looper an, the leed-operating cam. M and feeding-dog O, and its adjusting and supporting-devices,

and thepresser, its pin, t, and afid roller', s, when al1 are constrnctedand arranged as described.

In witness whereot',1 have hereunto signed my name, iu the presence ot' two subscribing witnesses.

VVit-nesses; ALONZO POR-TER.

i R. F. Oscoop,

GnAs. F. SPENCER. 

